Apparatus for the control of highway crossing signals



H. S. YOUNG Nov. 2, 1937.

Filed July 28, 1936 4 Sheets-Sheet l INVENTOR HenPy ouzzg.

HIS ATTORNEY a N 1% Q k J D U m @N MN|\\H m ww g N w n wag w w Wm E u 3 JD RR \w x 3; Q E

Nov. 2, 1937. H. s. YOUNG 2,097,827

APPARATUS FOR THE CONTROL OF HIGHWAY CROSSING SIGNALS Filed July 28, 1936 4 Sheets-Sheet 2 BY A by w

[116' ATTORNEY Nov. 2, 1937.

H. S. YOUNG APPARATUS FOR THE CONTROL OF HIGHWAY CROSSING SIGNALS Filed July 28, 19,36

4 Sheets-Sheet: 3

m I \q; N mi g, \--k s s a m 1*" a u v S E g a .s

w i i; E R .5 m 4 5 F? *1 w g3 g k g R FR E I v a: m

N M1 a L M -|l- W7C ,QINVENTOR g5 HemgZZI bmy m B. BY -|rk, 1 N

N HIS AITORNEY Nov. 2, 1937. H. s. YOUNG 7,8 7

APPARATUS FOR THE CONTROL OF HIGHWAY CROSSING SIGNALS Fil ed July 28, 1936 4 SheetsSheet 4 'N N & g r QT w =0 IT I LYZH 172% v mv NT-OR HenpgS. g.

T 4 BY HIS ATTORNEY apparatus effective to Fatent Serial No.

Patentecl Nov. 2, 1937 ?ATENT OFEQZE APPARATUS THE CONTROL OF HIGH- WAY CROSSING SIGNALS Henry S. Young, Wilkinsburg,

The Union Switch & Signal Company,

Pa., assignor to Swissvale, Pa, a corporation of Pennsylvania Application July 28,

13 Claims.

My invention relates to apparatus for the control of highway crossing signals, and particularly to apparatus controlled by a train approaching a highway crossing for governing the operation of c a highway crossing signal in accordance with the speed of the train.

A feature of my invention is the provision of noveland improved apparatus controlled by a train as it travels through two or more consecutive track sections in approaching a highway crossing for initiating the operation of a highway crossing signal when the train exceeds the limit of speed predetermined for each section. Another feature of my invention is the provision of prevent unnecessary operation of the time measuring means, usually employed in such apparatus, when a train recedes from the intersection. Another feature of the invention is the provision of apparatus of the type here involved wherewith operation of the time measuring means in response to a train approaching the highway crossing from either one of two routes is effected. Still another feature of the invention is the provision of apparatus which assures operation of the signal when a train moves over the crossing and then reverses its direction within the control limits to again approach the crossing. Furthermore, a feature of the invention is the provision of apparatus for control systems of the type here contemplated which is effective to check the track circuit of a time measuring track section. Other features and advantages of my invention will appear as the specification progresses.

I will describe several forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.

Apparatus controlled by a train as it travels two or more consecutive track sections in approaching a fixed location to operate a time measuring means for establishing a signal control if the train exceeds the limit of speed predetermined for any track section has been proposed in United States application for Letters 61,561, filed January 30, 1936, by George W. Baughman, for Railway signaling apparatus. My present invention may be consideredan improvement on the Baughman application.

in the accompanying drawings, Fig. 1 is a diagrammatic view of one form of apparatus embodying my invention. Figs. 2 and 3 are diagrammatic views of two other forms of apparatus for governing the highway crossing signal in accordance with the speed of a train approach- 1936, Serial No. 93,029

ing an intersection from either one of two track routes, and which forms of apparatus also embody my invention. Figs. 4 and 5 are diagrammatic fragmental views of apparatus that may be used in Figs. 1, 2, and 3 to check the track circuit of a time measuring track section.

In each of the several views, like reference characters designate similar parts.

Referring to Fig. 1, reference characters in and lb designate the track rails of a stretch of railway over which traffic normally moves in the directionindicated by an arrow, and which track rails are intersected at grade by a highway H. The track rails la and lb are formed by the usual insulated rail joints into five track sections 5T, 2T, 3T, ST, and ET, which a train travels successively in the order named in approaching the highway H when moving in the normal direction of traffic. A track switch SW is located in section ET and leads to a second track 5T from which trains may also approach the highway H-through the track sections 2T, 3T, QT, and 5T. These several track' sections are each provided with the usual track circuit which includes a source of current such as battery 2 and a track relay designated by the reference character R plus a prefix corresponding to the track section. For reasons to appear hereinafter, the two track relays iTR and 2TB comprise an interlocking relay which is of the standard type except for the fact thatthe backcontact M controlled by the .relay 2TH is closed whenever the winding of that relay is deenergized.

A slow release repeater relay indicated by the reference character PR plus a prefix corresponding to the associated track section is provided for each track relay except the track relay 5TB. Each repeater relay, except the repeater relay TPR-,--is controlled over a front contact of the associated tracl; relay and a front contact of the track relay next in advance. For example, repeater relay 4TB? is energized over a simple circuit which includes front contact is of the associated track relay TR and a front contact l5of track relay 5TB next in advance. Repeater relay ITPR is provided with an energizing circuit extending from the B terminal of any convenient source of current such as a battery, not shown, over front contact N5 of track relay ETR, wire i1, contact iii of r a switch circuit controller operatively connected with the switch SW and closed when the switch is set for trafiic to move from track ET, wire I9,'front contact 2?] of repeater relay ZTPR, Wire 2|, winding of relay I'I'PR, .andto the C terminal of the same source of current. It follows that with the switch SW set for trafiic to move from the track section iii, the repeater relay iTPR is deenergized, but that with section T unoccupied and switch SW set for traffic to move from track 6T, the relay iTPR is energized until such time as the train moving from track 5T advances to the right of the insulated rail joints 22 and shunts the track relay ZTR to cause its repeater relay ZTPR to be released.

The track section IT is a time measuring section, sections 2T and 3T are combined time measuring and operating sections, and sections 4T and ET are operating sections. As will appear hereinafter, the relative lengths of these several track sections are dependent upon the desired warning period of the highway crossing signal prior to the arrival of a train at the intersection, and also upon the minimum and maximum speeds of trains operated over this stretch of railway. The lengths of track sections IT, 2T, 3T, and 4T are directly proportional to a speed limit predetermined for each section, and the sections bear a selected relation as to the distance between the highway crossing and the near end of the section. These distances are such that substantially the same interval of time is required for a train to move from the near end of each section to the highway crossing at the respective predetermined speed limits of the sections. The lengths of the sections will be referred to again when the operation of the apparatus is described.

A highway crossing signal S is located adjacent the intersection and, as here shown, is an audible signal in the form of an electric bell. It will be understood, of course, that my invention is not limited to this one form of highway crossing signal, and other forms such as a flashing light, color light, gates or barriers may be used if desired. The immediate control of signal S is eifec-ted through the medium of two interlocking relays I EL and EL. The left-hand winding 3 of relay BL is controlled by the apparatus associated with the several track sections to the left of the highway H in a manner to be explained later. The right-hand winding 4 of relay IL may be governed by apparatus responsive to traffic approaching the highway H from the right and which apparatus is not shown for the sake of simplicity. The apparatus responsive to traffic conditions approaching the highway from the right may be similar to that associated with the track sections shown to the left of the highway. When the winding 3 of relay IL is deenergized prior to the deenergizing of winding 4, its back contact 5 is closed and a simple operating circuit for signal S is completed which causes the bell to sound a Warning. The left-hand winding 6 of relay 2L is controlled over a simple circuit which includes the front contact 'I of track relay 5TB for the section 5T adjacent the highway. The right-hand winding 8 of relay 2L may be controlled by a track relay (not shown) of a track section adjacent the highway to the right in a manner similar to the control of the winding 6. When the Winding 6 of relay 2L is deenergized prior to the deenergizing of winding 8 and its back contact 9 is closed, a second operating circuit for signal S is completed which also causes the bell to sound a warning.

The apparatus of Fig. 1 also includes a time measuring means designated as a whole by the reference character TM. This time measuring means may take diiferent forms several of which are well-known to the art. As ,here shown, the

contact II only after the winding of the relay has been energized a predetermined interval such as, for example, seconds, but that, upon deenergization of the winding of the relay, the

, contact arm I9 immediately drops from whatever position it has been advanced back to its normal position, that is, to the position illustrated in Fig. 1. A contact finger I2 is operatively connected with the contact arm I0, as indicated by a dotted line to check the normal position of arm I I], the arrangement being such that the contact finger I2 engages a stationary contact I3 only when the contact arm It occupies its full normal position. As will shortly appear, the relays of the time measuring means TM are successively operated as a train travels the sections IT, 2T, and ST, and, in turn, govern the signal control relay IL.

Normally, that is, when the track sections are all unoccupied, the track relays are each energized, the repeater relays, except relay I TPR, are all energized; and the winding 3 of relay IL is supplied with current over a circuit extending from the B battery terminal, front contacts 23, 24, and 25 of relays ETPR, 3TPR, and ITPR, respectively, wire 56, front contact 26 of track relay 5TR, winding 3, and to the opposite terminal C of the source of current, and winding 3 is energized. Relays SR, TER, and TEPR of the time measuring means are all normally deenergized and inactive.

In describing the operation of the apparatus of Fig. l, I shall assume that the desired warning period of signal S prior to the arrival of a train at the intersection is to 30 seconds, and that the minimum and maximum train speeds are and 120 miles per hour, respectively. To agree with this variation in the warning period (20 to seconds), the operating time of the relay TER is preferably 15 seconds. Under these assumptions, the track sections IT, 2T, 3T, GT, and ST are 1758, 1170, 786, 520, and 1044 feet in length respectively.

I shall first consider the operations which take place in response to a train moving from the track section IT toward the highway at the assumed minimum speed of 25 miles per hour or 36.7 feet per second. The train upon entering section IT shunts track relay ITR and that relay is released completing a circuit which includes the following elements; battery terminal B, back contact 21 of relay ITR, front contacts 28, 29, 35, 3|, 32, and 33 of relays ZTPR, 2TR, 3'IPR, 3TR, STPR, and 5TB, respectively, wire 55, front contact 34 of relay 5TR, check contact I2I3 of relay TER, winding of relay SR, and to the opposite terminal C of the current source, and relay SR is energized. Relay SR on picking up closes at its front contact 35 ashunt path around the check cont-act I 2I3, and at its front contact 36 completes an operating circuit for relay TER, and that relay is set into operation. Relay TER requires 15 seconds operating time to close its contact Iii-II, and, hence, when the train has advanced approximately 550 feet "in section IT:

(15 .36.'l) which is 1758 feet in length, relay TER closes its contact I9II and completes an energizing circuit for relay TEPR, and that relay is picked up. This circuit includes front contact 37 of relay SR as well as contact IEllI of relay TER. It is to be noted that with relays SR and TEPR picked up, the winding 3 of relay IL is provided. with two branch paths over either one of which it may receive current. One of these branch paths includes front contact .38 of .relay TEPR and front contact 26 of the track relay BTR, and the other branch path includes front.

contact 39 of relay SR and the front contact 26 of relay STR. 3

When this train advances and enters section 2T, the track relay ZTR is shunted and is released. The repeaterirelay ZTPR :is "now doenergized and releases at the endof-its slow release period. During the interval between the release of relay ZTR and the release of relay Z'IPR, the circuit for the control relay SR is open at front contact 29 of relay 2TR, and relay SR is deenergized and releases. relay TER is now without current and its contact arm it immediately drops to its normal position and the check contact l2-I3 is reclosed. When the repeater relay 2'I'PR releasesto close its back contact 49, a new energizing circuit for control relay SR is completed, and that relay is again picked up. This second energizing circuit includes the elements; 13 battery terminal, front contact 38 of relay TEPR, front contacts 25 and 24 of relays 4TPR and STPR, respectively, back contacts 46 and 4| of relays ZTPR and 2TR, respectively, and thence as traced for the first energizing circuit. The relay TEPR is provided with a slow release pericdwhich is sufficient to bridge the release period of relay ZTPR and the time required for relay SR to pick up and close its front contacts. With relay SR picked up, it is supplied with current over its own front contact 39 and the above traced second energizing circuit. The closing of front contact 35 of relay SR completes the shunt path around thecheck contact I2-I3, as before, and the closing of its front contact 36 completes the circuit for the relay TER, and a new operation for that relay-is initiated. While the release of the repeater relay 2TPR in response to the train entering section 2T opens at its front cont-act 23 the normal energizing circuit for winding 3 of relay IL, winding 3 is supplied with current first over the branch path including front cont-act 38 .of relay TEPR, and then over the branch path including front contact 39 of relay SR subsequent to the release of relay TEPR. It follows that entry of the train into section 2T is effective to cause the slow acting relay 'I'ER to be reset and a new operation thereof initiated, and to transfer the control of the winding 3 from its normal circuit to the two branch paths controlled by the time measuring means.

By the time this train traveling 25 miles per hour advances 550 feet in section 2T, the relay TER is again operated to close its contact IBI I, and relay TEPR is again picked up. When the train passes into section 3T and shunts track relay 3TR, that relay is released at once and its associated repeater relay STPR is deenergized and releases at the end of its slow release period. During the interval between the release of track relay 3TR and the release of the repeater relay 3TPR, the circuit for relay SR is open at front contact 3| of relay 3TB with the result that relays The slow acting.

SR and TER. are restored'to their'normal positions. The release of relay 3TPR to oloseits back contact 42 completes a new energizing circuit for the relay SR, and which circuit extends from B battery terminal over front contacts 38 and 25 of relays TEPR and 4TPR, respectively, back contacts 42 and 43 of relays 3TPR and 3TB, respectively, and thence as previously traced. Relay SR is again picked up and a new operation of relay TER is initiated. Since this train operating at 25 miles per hour consumes over 15 seconds in traveling through section 3T which is 736 feet in length, the slow acting relay TER is operated to close its contact Ill-II and pickup the relay TEPR prior to the arrival of the train at the entrance of the section 4T. The train upon passing into section 4T shunts track relay 4TR and deenergizes repeater relay 4TPR which releases at the expiration of its slow release period. During the interval between the release of relay 4TR and the release of relay 4TPR, the circuit for relay SR is open at front contact 33 of relay 4TR with the result that relays SR and TER are restored to their normal positions. When relay 4TPR releases to close its back contact 44, a new energizing circuit is completed for relay SR, and which includes back contacts 44 andfill of relays 4'I'PR and 4TR, respectively, as will be readily understood by an inspection of Fig- 1, and relay SR is again picked up. With relay SR picked up to close its front contact 39, relay SR is retainedenergized, and the winding 3 is supplied with current subsequent to the release of relay TEPR to open its front contact 38. When the train enters section 5T, it shunts track relay 5TR, and that relay upon releasing to open its front contact 26 deenergizes the winding 3 and operation of the highway crossing signal S is initiated. The opening of front contact 26 also removes current from the relay SR and that relay is restored to its normal position. It is to be noted that the slow acting relay TER is also operated during the time the train occupies the section 4T but operation of relay TER at this time performs no useful function. It follows that the warning period, prior to the arrival of the train at the intersection, is a little over 28 seconds since the section 5T is 1044 feet in length and the train speed is substantially 36.7 feet per second.

I shall next assume that a train approaches the highway crossing through section 5 T at the assumed maximum speed of miles per hour, or 176 feet per second. When this train enters section IT and shunts track relay ITR, that relay is released and completes at its back contact 21 the energizing circuit for control relay SR the same as described in connection with the first train. The relay TER is thus energizedto initiate its operation in response to the train entering the section IT. Relay TER, however, does not complete its operation and close contact I9II before the train advances through section IT and enters section 2T, since the train travels section IT in substantially 10 seconds, whereas the operating time of relay TER is 15 seconds. Consequently, relay TEPR is not picked up prior to the shunting of the track relay ZTR with the result that when the track repeater relay ZTPR releases, the relay SR is not reenergized and the winding 3 is at once deenergized to initiate the operation of the highway crossing signal S. The warning period for signal S prior to the arrival of this train at the intersection is substantially 20 seconds since the total distance from the exit end of section ITto the intersectionis 3520 feet, which is 7.5;

the distance a train operated at 176 feet per second advances in 20 seconds. I

It is apparent, therefore, thatfor all trains eX- ceeding miles'per hour in section IT, the operation of signal S is started when the head end of the train enters section 2T, since such trains reach the exit end of section IT in less than 15 seconds, the operating time of the relay TER. The operating time of the highway crossing signals for such train speeds is from 20 to 30 seconds, since the distance from the highway to the near end of section IT is substantially 3520 feet. For trains moving less than 80 miles per hour but over 53.4 miles per hour, the operation of the signal S is started in response to the head end of the train entering section 3T since at such train speeds the train will advance through section 2T in less than 15 seconds. Again, the operating time of the signal S is from 20 to 30 seconds since the distance between the highway andthe near end of section 2T is substantially 2350 feet. I

For trains moving less than 53.4 and over 35.6 miles per hour, the operation of the signal S is initiated in response to the head end of the train entering section 4T, since at such train speeds a train will pass through section ST in less than 15 seconds. The distance between the highway and the near end of section 3T being substantially 1564 feet, the warning period from 20 to 30 seconds for the signal S is assured for this range of train speeds. For train speeds between 35.6 and 25 miles per hour, the operation of the signal S is delayed until the train enters the final operating section 5T. Again, the distance between the highway and the near end of section 4T being substantially 1M4 feet, the warning period is from 20 to 30 seconds.

The above described operation of the apparatus of Fig. 1 is similar to the operation for the apparatus of the above cited Baughmansystem. I shall now point out improvements in the operation accomplished by the apparatus of' Fig.' 1. Taking the case of a train operated from track 6T toward the highway. Whenthe switch SW is reversed and contact I8 is closed,the repeater relay ITPR is picked up to close its front contact 45 and supply current to the winding 3 of the controlrelay IL in parallel with the path which includes the front contact 23 of relay Z'I-PR. When the train moving fromxtrack 6T advances to the right past the insulated joints 22 and shunts the track relay Z'IR, the repeater relay 2TPR is deenergized and releases at the end of its slow release period. Relay ZTPR, upon releasing to close its back contact 40, completes an energizing circuit for the control relay SR of the time measuring means. This circuit may be traced from B battery terminal over front contact #35 of relay ITPR, back contact 40 of relay ZTPR, back contact 4| of track relay 2TH, front contacts 3!], 3!, 32, and 33, wire 55, front contact 36, checkcontact l2-|3, winding of relay SR, and to the C battery terminal. With relay SR once picked up, it is retained energized by current supplied over its front contact 39subsequent to the release of the repeater relay ITPR, which latter relay is deenergized when relay ZTPR releases to open front contact 20. It is apparent, therefore, that the. time measuring means is set into operation in response to the train entering the section 2T from the track ST and is successively operated as the train advances through the sections 2T, 3T and AT thesame as described in the case of a train operating from the section IT, and'the operation of the highway crossing signal S is governed in accordance with the train speed the same as described hereinbefore. It is to be noted that the contact l8 may be omitted, and the wires I! and i9 joined together and the relay ITPR normally energized.

A train approaching the highway H from the right, as viewed in Fig. 1, and receding from the crossing through the track sections of Fig. 1 would operate the track relays, but operation of the signal S by the relay IL is avoided due to the interlocking feature of that relay. Energization of the control relay SE. of the time measuring means is avoided under such traffic conditions by virtue of the control circuit for relay SR. being held open at the respective track relays and track repeater relays. When a train moving from right to left has cleared all the track sections except the initial time measuring section IT, the energizing circuit for relay SR is held open at the back contact 21 of relay ITR. and unnecessary operation of the time measuring means is avoided due to the interlocking between the relays ITR. and 2TB. When a train receding from the crossing passes over switch SW to the track 6T unnecessary operation of the time measuring means while the train is in section 2T is avoided since relay ITPR is now deenergized due to its .circuit being open at the front contact 26 of relay 2TPR.

When a train, such as a work train, moves over the crossing from the right, recedes from the crossing through section 5T, stops in one of the other track sections, for example, section eT, and.

then reverses its direction to approach the highway from the left, the interlocking relay IL is ineffective to operate the signal S in response to this train approaching the highway due to the interlocking feature of that relay. The second interlocking relay 2L, however, is reenergized and restored to its normal position subsequent to the train vacating the section 5T, and hence when the train, after reversing its direction, enters section 5T, 'the winding 6 of relay 2L is deenergized and its back contact 9 is closed to complete an operating circuit for the signal S.

In Fig. 2, the track layout and apparatus is the same as in Fig. 1, except a track section X is formed in track 6T, the repeater relay ITPR. is omitted, and relay TEPR is provided withan auxiliary pickup circuit. Track section X is preferably short and is provided with a track circuit which includes a track relay XTR. The auxiliary pickup circuit for relay TEPR may be traced from B battery terminal, over front contacts'dfi and 41 of relays ITR and ZTPR, respectively, wire 48, back contact 49 of relay XTR to wire 50, or by contact 51 operated by switch SW and closed when the switch is reversed, to wire 59, thence over front contacts 5!, 52', and 53 of track relays 3TB, 4TB, and 5TB, respectively, wire 54, winding of relay TEPR, and to the opposite terminal C of the current source. The operation of the apparatus of Fig. 2 in response to a train approaching the highway through track section IT is essentially the same as in Fig. 1, and need not be repeated. A train moving from track 6T toward the highway and entering section X shunts track relay XTR, and that relay upon re-- leasing completes the auxiliary pickup circuit for relay TEPR which picks up and closes its front contact 38. When the train advances to the right of section X and shunts track relay 2TB and causes the release of the repeater relay ZTPR, the normal energizing circuit for winding 3 is open at front contact 23 of relay Z'I'PR, but winding 3 is now supplied with current over the branch path including front contact 38 of relay TEPR.

In the event the switch SW is reversed prior to a train entering section X, the above-traced auxiliary circuit is completed at contact 51 and relay TEPR is picked up. Release of relays ZTR and 2TPR to close back contacts ii and 40 in response to the train entering section 2T completes the energizing circuit for relay SR and, that relay is picked up to initiate an operationof the time measuring means. Relay TEPR is released subsequent to the release of repeater relay ZTPR and the opening of its front contact 2!), but relay SR is retained energized and winding 3 is supplied with current over front contact 39 of relay SR subsequent to release of relay TEPR. If the speed of the train advancing from contact 6T is below a predetermined speed, the time measuring device completes its operation and again picks up relay TEPR prior to the train entering track section 3T, the section 2T thus serving as the initial time measuring section. From this point on the operation of the apparatus of Fig. 2 for a train approaching the highway from track GT is substantially the same as previously described for Fig. 1. It is to be seen, therefore, that the apparatus of Fig. 2 is effective to govern the operation of the highway crossing signal S in accordance with the speed of a train approaching the highway from either track lT or from track 6T.

In Fig. 3, the apparatus differs from that of Fig. 1 in that the repeater relay ITPR is omitted and the energizing circuit for relay SR is provided with a branch path which includes the closed position of a contact 61 operated by switch SW. It is clear that when switch SW is reversed to permit a train to move from track iiT toward the highway and contact 6? is closed, the relay SR is picked up and operation of the time measuring means is effected. Resetting of the time measuring means and initiating a new operation thereof in response to a train entering section 3T is effected the same described for Fig. 1. It is clear, therefore, that the apparatus of Fig. 3 is operative to govern the signal S in accordance with the speed of the train approaching the highway from track 5T as in previous cases, the section 3T this time serving as the initial time measuring section.

In Fig. i, a short track section Y is located at the entrance of the time measuring section IT. Track section Y may be short, say of one rail length, and is provided with a track circuit which includes track relay YTR. The track section Y being short, the track circuit can be readily maintained in proper working order. A slow pickup relay U is controlled over a back contact 58 of track relayYTR. The relay'U is proportioned and adjusted to have a slow pickup period of the order of 0.5 second. The energizing circuit for relay SR is now extended from the hack contact 2'? of track relay lTR to the B terminal of the current source over front contacts 59 and 66 of relays U and YTR, respectively, in parallel.

With the apparatus constructed as shown in Fig. l, a failure of the track circuit for section IT when no train is approaching the highway may cause relay STR to be released and its back contact 21 closed with the result that an operation of the time measuring means is effected. Under such circumstances, the control of the highway crossing signal S would be shortened by the length of the track section 2T. With the apparatus constructed as shown in Fig. 4, a failure of the track circuit for the section IT when no train is approaching the highway might result in anoperation-of the time measuring means the Same asin Fig. 1. A train approaching the highway H from the left shunts track relay YTR and causes relay U to be picked up at the end of its slow pickup period. During the interval between the release: of track relay YTR to open its front contact '50, and the picking up of relay U to close its front contact 59, the circuit for relay SR is held/open. and relay SR is released, restoring the time measuring means to its normal position, in the'event it had completed an operation due to a failure of the track circuit of section. IT. With relay U picked up and track relay iTR down in response to a train passing over section Y and entering section ET, the relay SR is reenergized and a new operation of the time measuring means is initiated to effect a control over the highway crossing signal in accordance with the speed of the train operating through the section l'I'. When the rear of a train passes to the right of section Y, theenergizing circuit for relay SR is not interrupted since the contact Gil of relay YTR is closed prior to the opening of the front contact 59. of relay U.

In Fig. 5, a short track section Y is located adjacent the entrance of the time measuring sectionJT the same as in Fig. 4. In this form of the invention, a slow release relay V is provided and is controlled over a pickup circuit including terminal B of the current source, back contact 6! of track relay YTR, front contacts 62 and E3, of relays ITR and ZTR, respectively, Winding of relay V, .and to the C battery terminal. Relay V. is retained energized over a stick circuit including its own front contact 84 and back contact 65 of relay ITR as will be readily understood by an inspection of Fig. 5. A front contact 66 ofrelay. V is interposed in the energizing circuit for relay SR.

With the apparatus constructed as illustrated in Fig. 5and a failure of the track circuit for section IT occurs that might cause relay ITR to be released, the relay SR of the time measuring means is not energized since its circuit is held open at the front contact 66 of relay V. Under such circumstances, and a train advances over section Y-and enters the measuring section IT, relay V remains deenergized since its pickup circuit is held open at front contact 62 of relay ITR. As a'result of relay V not being picked up, the time measuring means remains inactive during the time the train is traveling through the section IT. When" the train enters section 2T and shunts track relay ZTR to deenergize the repeater relay ZTPR, the winding 3 of the signal control relay is deenergized due to the opening of front contact 23 and due to the fact that the branch paths for thewinding 3 controlled by the time measuring means is now open. It follows that operation ofthe highway crossing signal is immediately effected in response to the train entering the section 2T in the event the track circuit for section IT should fail.

Although I have herein shown and described several forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of railway track intersected by a highway and comprising a track switch to permit a train to approach the crossing from either of two diverging routes, a highway crossing signal located at the crossing,-a first and a second timing track section and an operating track section arranged in the-order named between the switch and the crossing with the first timing section at the switch and including portions of the track rails of each route, a track circuit for each of said track sections'including a track relay, operating means controlled bythe reiay of the second timing section and by the relay of the operating section to start operation of the signal in response to a train entering the respective section,.time measuring means having a predetermined operating time, circuit means governed by the track relay of each of the timing sections to initiate an operation of the time measuring means, means controlled by the time measuring means to delay the operating means in starting operation of the signal when it has completed an operation, and a circuit controller having connection with the switch to modify the control of said circuit means over the time measuring means when the switch is set for a particular one of the routes.

2. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, a first and a second track section which a train travels successively in the order named in approaching. the crossing when moving in the normal direction of traific, a track circuit for each section including atrack relay, operating means controlled by the track relay of the second section when shunted to operate the signal, time'measurin'g means effective at times to modify the control of the operating means, a control circuit for operating the time measuring means and including a back contact of the track relay of the first section and a front contact of the track relay of the second section, and means controlled by thev track relay of the second section in response to a, train receding from the crossing to prevent said back contact of the track relay of the first section from closing to complete the control circuit for operating the time measuring means when the train receding from the crossing occupies said first section.

3. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, a first and a second track section whicha train travels successively in the order named in approaching the crossing when moving in the normal direction of trafiic, a track circuit for each section, an interlocking relay having a first winding interposed in the track circuit of the first section and a second winding interposed in the track circuit of the second section, operating means including a front contact controlled by said second winding to pperate the signal in response to a train occupying said second section, time measuring means effective at times to modify the control of the operating means, and a control circuit for the time measuring means including a full down contact of the first winding of said interlocking relay. v

4. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, two track sections formed on one side of the crossing, a track circuit for each section including a track re1ay,-a first and a second interlocking relay, a control'circuit for a winding of the first interlocking relay and including a front contact of each of the track relays in series, a control circuit for a winding of the second interlocking relay and including a front contact of the track relay of the section nearer the crossing only, and an operating circuit for said signal including full down contacts of said windings of said interlocking relays in parallel.

5. In combination, a stretch of railway track intersected by a highway, a plurality of consecutive track sections which a train travels successively in approaching the crossing when moving in the normal direction of trafiic, a track circuit for each section including a track relay, a highway crossing signal located at the crossing, a slow acting means, control means controlled by the track relays to operate said slow acting means, a first operating means controlled jointly by the track relays and the slow acting means to operate the signal in accordance with the speed of a train, means controlled by a train passing over the crossing and receding through the sections against the normal direction of traffic to render said operating means ineffective to operate the signal, and a second operating means for operating the signal and including a front contact of the track relay for the section adjacent the crossing only whereby the signal is operated by said receding train reversing its direction and approaching the crossing. a

6. In combination, a stretch of railway track intersected by a highway, a plurality of consecutive track sections which a train travels successively in approaching the crossing when moving in the normal direction of tramc, a track circuit for each section including a track relay, a highway crossing signal located at the crossing, a slow acting means, control means controlled by the track relays to operate said slow acting means, a first interlocking relay, a first operating circuit for the signal and including a full down contact of one winding of said interlocking relay, a control circuit for said one winding governed jointly by the track relays of the sections and the slow acting means whereby said operating circuit is made active to operate the signal in accordance with the speed of a train approaching the crossing in the normal direction of trafiic and is ineffective to operate the signal when a train recedes from the crossing through the sections, a second interlocking relay, a second operating circuit for the signal including a full down contact of one winding of said second interlocking relay, and a control circuit for the last mentioned winding including a front contact of the track relay for the section adjacent the crossing to operate the signal when a receding train reverses its direction and again approaches the crossing.

'7. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, a timing track section and an operating track section which a train travels in the order named in approaching the crossing, a track circuit for each section including a track relay, an operating circuit for said signal controlled by the track relay of the operating section to start operation of the signal when a train enters that section, a time measuring means eilective when energized a predetermined time interval to delay the operating means in starting operation of the signal, an energizing circuit for the time measuring means including a back contact of the track relay of the timing section, an auxiliary track section located adjacent the entrance of the timing section, a track relay for said auxiliary sections, a slow pickup relay energized over a back contact of the last men.- tioned track relay, and means to interpose a front contact of the slow pickup relay and a front contact of the last mentioned track relay in parallel in said energizing circuit.

8. In combination, an insulated section of rail- Way track, a track circuit for said section including the track rails and a normally energized track relay as well as a current source, a signaling device, a control circuit including a back contact of said track relay for operating said signaling device, another track circuit including the track rails adjacent one end of said track section and a normally energized track relay as well as a current source, a slow pickup relay, a pickup circuit for said slow pickup relay including a back contact of the last mentioned track relay, and means to interpose a front contact of the slow pickup relay and a front contact of the last mentioned track relay in said control circuit in parallel.

9. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, a timing track section and an operating track section which a train travels in the order named in approaching the crossing, a track circuit for each section including a track relay, an operating circuit for said signal controlled by the track relay of the operating section to start operation of the signal when a train enters that section, a time measuring means effective when energized a predetermined time interval to delay the operating means in starting operation of the signal, an energizing circuit for the time measuring means including a back contact of the track relay of the timing section, an auxiliary track section located adjacent the entrance of the timing section, a track relay for said auxiliary section, a slow release relay, a pickup circuit for said slow release relay including a back contact of the track relay of the auxiliary track section and front contact of the track relay of the timing section, a stick circuit for the slow release relay including a back contact of the track relay of the timing section, and a front contact of said slow release relay interposed in said energizing circuit.

10. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, a first and a second timing track section and an operating track sec-.

tion arranged in the order named to one side of the crossing, a track switch located in said second timing section leading to a diverging track, a track circuit foreach track section including a track relay, operating means controlled by the relay of the second timing section and by the relay of the operating section to start operation of the signal in response to a train entering the respective section, time measuring means having a predetermined operating time, circuit means governed by the track relay of each of the timing sections to initiate an operation of the time measuring means, means controlled by the time ZIJGZLS means to delay the operating means in starting operation of the signal when it has completed its operation, and a circuit controller connected with the switch to render the track relay of said second timing section ineffective to control said operating means when the switch is set for traffic from the diverging track.

ii. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing; a first, a second, a third and a fourth track section arranged in the order named to one side of the crossing; a track switch located in said second section leading to a diverging track, a track circuit for each section including a track relay, operating means controlled by the relay of the second and third and fourth sections to start operation of the signal in response to a train entering the respective section, time measuring means having a predetermined operating time, circuit means governed by the relay of the first and second and third sections to initiate an operation of the time measuring means in response to a train entering the respective section, means controlled by the time measuring means to delay the operating means in starting operation of the signal when it has completed its operation, and means including a circuit controller connected with the switch operative when the switch is set for traffic from the diverging track to render the relay of the second section inefiective to control said operating means and to render the relay of the first and the second section inefiective to initiate operation of the time measuring means.

12. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing; a first, a second, a third and a fourth track section arranged in the order named to one side of the crossing; a track switch located in said second section leading to a diverging track, a track circuit for each section including a track relay, operating means controlled by the relay of the second and third fourth sections to start operation of the signal in response to a train entering the respective section, time measuring means including a controlled relay picked up after a predetermined operating time and effective when picked up to render said operating means ineffective, circuit means governed by the relay of the first and second and third sections to initiate an operation of the time measuring means in response to a train entering the respective section, and means controlled by a train on said diverging track and including a circuit controller connected with the switch to pick up said controlled relay to render the second section ineffective to control the operating means.

13. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the crossing, a timing track section and an operating track section which a train travels in the order named in approaching the crossing, a track circuit for each section including a track relay, an operating circuit for said signal controlled by the track relay of the operating section to start operation of the signal when a train enters that section, time measuring means biased to an initial position and moved to an active position when energized a predetermined time interval to delay the operating means in starting operation of the signal, an energizing circuit for the time measuring means including a back contact of the track relay of the timing section, traffic controlled means located adjacent the entrance of the timing section, and means governed by said trafiic controlled means to momentarily open said energizing circuit torestore the time measuring means to its initial position in the event of a failure of the track circuit of the timing section.

HENRY S. YOUNG. 

